Question

20) Consider the two beakers labeled A and B. Beaker Acontains 1 mole of iron atom Beaker B contains 1 mole of lead atoms. Which statement concerning these samples known with certainty? mole of iron atoms, and 20) Beer Besker A) Beakers A and B contain an equal volume of atoms. B) Beakers A and B contain samples with the same density. C) Beakers A and B contain an equal number of atoms. D) Beakers A and B contain equal masses of atoms. E) None of these are correct. 21) 21) Which statement correctly describes what is happening in the reaction shown below? 2Mg(3) + S268) - MgS(3) A) Mg is oxidized. B) Mg is the oxidizing agent. C) S2 loses electrons. D) MgS gains electrons. E) MgS is the reducing agent. 22)- 22) The fluoride rinse in dental offices usually contains sodium fluoride, Sodium fluoride can be prepared from the reaction between sodium metal and fluorine gas. Which of the following properly represents the balanced chemical equation for this reaction? A) 2Na(s) + F26) - 2Na2F(5) B) Na(s) + F(8) -NaF(5) C) 7Na(s) + F(e) - Na7F(3) D) Na(s) + F2(8) - NaF2(3) E) 2Na(s) +F2(8) - 2NaF(3) 23) – 23) A given mass of oxygen at room temperature occupies a volume of 500.0 mL at 1.50 atm pressure. What pressure must be applied to compress the gas to a volume of only 150.0 mL? A) 150 atm B) 0.500 atm C) 1.50 atm D) 500 atm E) 5.00 atm

Answer 1

20 xotion nomises s) + S, C11 - Reduction TT Coxidation rembes eis de creare) I oxidation Coxidation number is increased) I Ma in oxidized and S. is reduced ng loker electrons and s gaino electrone. being oxidized Reducing agent : = specier ng Oxidizing agent species being reduced sz =